Friday 31 August 2012

Exercise oficially extends life

Following a healthy lifestyle can lead to a longer life, even among people who are already well into their 70s, new research shows.

Getting regular exercise, staying engaged with friends and family, and abstaining from smoking were all associated with longer life in a study that followed people in their mid-70s and older for close to two decades.

These healthy traits apparently added, on average, five years to women’s lives and six years to men’s.
The study is among the first to identify specific lifestyle behaviors associated with longer life, even among people with chronic health problems and those over the age of 80, researchers say.

“Our results suggest that encouraging favorable lifestyle behaviors even at advanced ages may enhance life expectancy,” concluded the researchers from Sweden’s Karolinska Institute and Stockholm University.

The study, published in the journal BMJ, included about 1,800 people who were followed for 18 years from the mid-1980s.

Everyone in the study was 75 years old or older at enrollment, and 9 out of 10 (92%) died during the follow-up. Half lived for 90 years or longer, with women being more likely to survive to this age than men. Those who lived longer were also more likely to be highly educated, participate in physical and non-physical leisure activities, have rich social networks, and engage in regular exercise.

Physical activity was the single biggest predictor of longevity. People who regularly swam, walked, or performed other exercise lived an average of two years longer than people who did not. Longevity in former smokers was similar to that of people who had never smoked, but 4 out of 5 former smokers quit between 15 and 35 years before entering the study.

People with the healthiest lifestyles lived an average of 5.4 years longer than those with the least healthy lifestyles. Even among people over the age of 85 and those with chronic health conditions, a healthy lifestyle appeared to prolong life by four years. The study did not include information on diet, so it is unclear how healthy and unhealthy eating behaviors affected life span.

The researchers also didn't know lifestyle behaviors prior to old age. Despite these limitations, Gisele Wolf-Klein, MD, says the findings add to the evidence that it is never too late to improve health and prolong life.
Wolf-Klein is director of geriatric education for the North Shore-LIJ Health System in New Hyde Park, N.Y.

“It has been known for a long time that adjusting lifestyle behaviors at any age can be beneficial in terms of health and survival,” she says. She cites as an example her mentor in geriatric medicine who was a smoker until he had a massive heart attack in his mid-70s. “He gave up smoking ‘cold turkey’ after that and began exercising on a stationary bicycle 30 minutes every day,” she says. “He is still doing it at the age of 94.”

Thursday 23 August 2012

30 mins of Exercise a day as good as 60, in some cases.

A new study at the University of Copenhagen in Denmark has found that sedentary, slightly overweight healthy young men, who worked up a sweat exercising 30 minutes daily for three months, lost a similar amount of weight and body fat as those who did 60 minutes of daily exercise.

The researchers describe the findings of their randomized controlled trial in a study reported online recently in the American Journal of Physiology.

The researchers suggest one reason for the surprising result is that the exercise felt "doable" for the participants in the 30 minutes a day group, who even felt afterwards that they could have done more. In contrast, the 60 minutes a day group probably compensated by eating more, therefore losing less weight than expected.

This second point would fit in with the results of previous research that the researchers point to in their background information. This suggests that the reason exercise often produces a disappointing amount of weight loss is because a diet-induced negative energy balance (where calories consumed aren't enough to cover daily energy needs) often triggers "compensatory mechanisms", such as lower metabolic rate and increased appetite.

Perhaps 60 minutes of exercise results in more overcompensation than 30 minutes. On average, the men who exercised 30 minutes a day lost 3.6 kg in three months, and those who exercised 60 minutes a day lost 2.7 kg. The reduction in body fat was about 4 kg for both groups.

The result is significant because 40% of Danish men are thought to be moderately overweight. Overcoming barriers to exercise in a group that does none at all should be easier if the aim is to attain 30 minutes a day than 60 minutes a day.

The study is part of an interdisciplinary trial called FINE, a Danish acronym for physical activity for a long healthy life, which has generated strong data in a group of 60 or so participants.

For the study, the researchers randomly assigned each of 62 healthy, sedentary, moderately overweight young men to one of three groups: a high exercise group (burning about 600 kcal per day with about 60 minutes of aerobic exercise), a moderate exercise group (300 kcal per day, 30 minutes exercise), and a control group that continued to be sedentary.

They monitored the men as they followed their program for 13 weeks.The participants trained every day through the study period. The training sessions were planned to produce a light sweat, but the participants were also instructed to increase the intensity three times a week.

The results showed that body weight went down by 2.7 kg in the high exercise group, and 3.6 kg in the moderate exercise group. Fat mass went down by 4.0 kg and 3.8 kg respectively.